Study of a Large-tailed Nightjar Carcass

posted in: Morphology-Develop. | 6

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“On 23rd Aug 15, a young friend named Caleb, stopped me and pointed towards the base of a palm tree as we were walking along Jalan Loyang Besar, towards Pasir Ris Carpark A (above). The pointed wing of a Large-tailed Nightjar (Caprimulgus macrurus) with a prominent white patch caught his attention. After calling the hotline of a local nature group that collects bird carcasses, I was advised to bury the bird as all their staff were very busy that Sunday afternoon and could not collect the bird specimen. This organisation did ask for the location of the dead bird for their records.

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“I decided to bring it home, photographed it; bury it and then do some research of this species. I was once fascinated by the complex and varied camouflage design of this bird, especially the scapular feathers, that I painted it with acrylic paint on canvas in 2009 to study its pattern (above).

“Here are some interesting facts I discovered in my brief research.

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“Firstly I learnt that this was a male bird, indicated by the prominent white patch on the primary feathers and the 2 outer tail feathers, when seen from the top or dorsal view of the bird (above). It is even more obvious when seen from the belly view of the bird (below). The female bird has white patches that are smaller and buffed coloured, (source: A field guide to the birds of South-east Asia by Craig Robson).

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“Next I went to research on the function of the wings, tail and and feathers. The long pointed wings and long tail (pic. 3-4 above)), make this bird an acrobatic and silent flyer (source: Sungei Buloh Wetland Reserve, Large-tailed Nightjar written by Ria Tan). The pointed wings reminded me of the Peregrine Falcon, a highly acrobatic hunter; hence its other name is the Night hawk. The silent flyer reminds me of the owls that need to have specially modified feathers to spring a surprise on their prey.

“The camouflage patterns on their wings and body serves to disguise them among dried leaf litter as they dwell on the ground most of the time. I tend to believe the camouflage feathers of the dorsal wings, body and tail of the adult birds also serve as a secondary function, to protect the chicks and eggs that are hidden in the adult bird’s down feathers during nesting.

“The wings are also well known as a weapon to distract the predator away from the nest. The female bid is especially known to behave this way by faking a broken wing and slowly moving away from the nest. Perhaps the patterns, size and shape of the wings help to exaggerate this behavior more effectively.

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“I photographed the down feathers to show how dense and fluffy they are (above). The down feathers acts as curtains for the chicks move within the confines of the adult birds belly for warmth and protection.

“The tail is beautifully patterned and long, with varied feather patterns (see pic 3-4 above). The function of the white patches on the tail of the Male adult bird can perhaps be best understood if we make a reference to the male Long-trained Nightjar found in South America. These elongated outer rectrices or tail feathers, 48-68cm (19-27 inch) of the male Long-trained Nightjar, can be more than twice its body length. They are used in courtship display, during which the males puff up their throats and raise their tail feathers at the right angle, where the white inner edges form a conspicuous V (source: Illustrated encyclopedia of birds by Birdlife International).

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“I also noticed a new budding, rounded tail feather (above). It’s short, white and prominent and has 2 feather shafts beside it. These shafts look either broken or could be new feathers. Could this single rounded feather be the white outer tail feather or a middle dark tail feather that will eventually grow dark when it is fully grown?

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“I was also fascinated by the bristles at the base of the beak, known as rictal bristles (above). When I touched the rictal bristles with my gloved finger, they felt very stiff. These bristles serves as a funnel to channel insects into the beak, detect the prey so the bird knows when to shut it’s mouth and deflect insects from the eyes (source: Sungei Buloh Wetland Reserve, Large-tailed Nightjar, by Ria Tan).

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“The feet of this bird is seldom seen when it is perched on branches or on the ground (above). It is interesting to notice that this Nightjar has a serrated comb-like portion on the inner middle toe (below), left side of picture. This is similar to other birds such as some bitterns, owls and pelicans. This serrated comb-like portion may be used to comb out insect debris from their facial feathers, source: Sungei Buloh Wetland Reserve, Large-tailed Nightjar written by Ria Tan).

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“Being a very visual person, I was very drawn to the interesting individual patterns on all the feathers. Just to highlight this, I took pictures of several down feathers (below, pic. 10-12). The designs seem to give the impression that they were individually hand painted on. One of my favorite feather patterns is pic. 9 above. As an artist, it will take me a couple of hours or more to paint it realistically as it is shown in pic 9. Imagine painting the whole bird (see pic. 8). One of my favorite feather patterns is pic. 10. As an artist, it will take me a couple of hours or more, to paint all the intricate details of this tiny feather. Imagine painting the whole bird, see pict 8. Therefore this bird will always be one of my all-time favorite bird to study, sketch and paint.”

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Thong Chow Ngian
Singapore
23rd August 2015

6 Responses

  1. Good pictures & well-written, informative article.
    No forensics on how or why it died?

    • Thong Chow Ngian

      Hi Kimosabe
      I called an organisation that does forensic testing on the cause of death but all their staff were busy that day.
      I noticed the neck feathers were very ruffled and neck seems broken.

      • Broken neck suggests some form of blunt force trauma. Was it found anywhere close to a building? Might have flown into a window and died from the collision.

        • Thong Chow Ngian

          Hi Ivan. The bird was found at the bottom of a palm tree. This tree is outside a fence that belongs to a condo called the Lighthouse.Thks for asking.

  2. Liao Weijie

    Excellent documentary Chow! I learned so much from your article.

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